


Nico Di'Angelo and the Order of the Phoenix

by eatyourhartout



Category: Harry Potter - J. K. Rowling, Percy Jackson and the Olympians & Related Fandoms - All Media Types, Percy Jackson and the Olympians - Rick Riordan
Genre: Alternate Universe - Canon, Book 5: Harry Potter and the Order of the Phoenix, Crossover, During Canon, Friendship, Gen, Harry Potter is a Horcrux, Hogwarts, Horcrux Hunting, Humor, Magic, One-Sided Nico di Angelo/Percy Jackson, Post-The Last Olympian (Percy Jackson), Pre-The Lost Hero (Heroes of Olympus), Shadow Travel (Percy Jackson)
Language: English
Status: In-Progress
Published: 2018-11-12
Updated: 2019-04-22
Packaged: 2019-08-22 19:32:25
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 8
Words: 4,958
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16604165
Author URL: https://archiveofourown.org/users/eatyourhartout/pseuds/eatyourhartout
Summary: Olympus is closed and Death has taken an abrupt vacation. Nico is left with more chores than ever, helping his father Hades run the Underworld in secret.This time his chores take him all the way across the Atlantic; London to be exact.He isn't sure how many more complications he can handle, with Thanatos MIA, a resurrected sister and a slippery soul to punish.Post Last Olympian, Pre-Giants war.





	1. Chapter 1

Nico frowns as he shrugs tries to figure out the IPad in front of him. It was  _really_  inconvenient for Thanatos to go missing. But then again, it did have a few advantages. He thought back to his sister. His new one.

Hazel Levesque.

She was a sweet girl. And it was nice to relate to someone, to feel out of time. But he supposed it was worse for Hazel, seeing that she remembered all of her life from  _before_.

And she was  _technically_  born before him. Nico was born a couple years after Hazel. But he was physically older and, if he was honest it made his brain hurt to think about it to much. So he did what he did best, and shoved the thoughts into a box neatly labeled  _Being from the 40s sucks_  and buried it deep down, right next to several other boxes ( _Bianca, Momma, Percy)_. He pushed the boxes away, focusing on other things instead.

Hazel.

Yes.  _Right._  

Nico was glad that the Roman Praetor, Jason Grace was so kind to her. While Camp Jupiter was less overwhelming for the recently resurrected daughter of Pluto, the modern world and it's behaviors are still a major adjustment to make. And he is running his own errands for their father more and more often now; leaving him with precious little time to help her adjust. Hopefully the Romans could do what he can't. 

Hades seemed distracted lately. Something major is occurring on Olympus. So major, that Hades is welcomed in New York outside the Winter Solstice. Any instructions he sends to Nico is in secret, as Zeus had recalled all the gods, _even_ his father, and closed Olympus. But the Underworld is nothing like the sky. It needs constant management and when Death decided to take an impromptu vacation, Nico had to step up.

Which is why the son of Hades found himself in the middle of London holding a piece of technology he doesn't understand trying to find an abomination. A Tom Riddle seems to not only have cheated death, but was actively looking to achieve immortality.

A crime that is not only an insult to his father, but against Olympus itself. This was one of the few mission's that even the thick skulled Zeus was allowing to be directly handed down to a half blood. And Nico could do it IF ONLY THE ZEUS BE DAMNED THING WOULD TURN ON! Nico nearly tossed the IPad away from him in disgust when he hit a small button on the side and it suddenly turned on.

"Oh. So that's how you do it." He muttered to himself, feeling foolish.


	2. Chapter 2

After a lot of swearing and struggling, Nico finally figured out how to use Thanatos's IPad. After he turned it on with the little button on the side, he found that by tapping the little round button on the front, he could light the screen up. The device scanned his aura to admit him. Then Nico pressed the square with the picture of a screech owl on it, one of his father's symbols.

That launched a program, that after it opened, he could scroll through the names of souls he needed to collect by swiping down the screen or by carefully typing in a name into the search bar at the top of the screen.

It sounded _so_ simple. And yet it was so incredibly difficult. All he wanted to do was reap this  _one_  soul. Just one. Anything else he could worry about later. But  _this_  idiot decided to jam up the paperwork. Which is why Nico had to go out and personally deal with a death.

He hoped this Tom Riddle really suffered in the Fields. Nico was dragged out of his warm bed for this.


	3. Chapter 3

He finally found the address in the IPad thing. But now he had to figure out where 12 Grimmauld Place is. Nico frustratedly tapped at the screen, unsure of what to do. The shadows were finally creeping up the walls, the sun setting. He really wanted to be done before it got too late, knowing that he was supposed to go check on Hazel's progress at Camp Jupiter. Then Nico smacked himself in the face.

Shadows.  _Duh_.

Sometimes Nico worried that his obtuse cousin was rubbing off on him. Nico frowned and locked away the surge of nervous  _something_  that always comes with thinking about his green eyed hero. Nico's heart does an odd skip-bump before Nico shoves the thought away.

He focuses on his goal, Grimmauld Place, before stepping into the shadows.


	4. Chapter 4

He's irritated. Nico had found the house, but it the door WAS MISSING ITS DOORKNOB. Nico was going to make sure this Tom Riddle suffered greatly for all the aggravation he was causing.

Maybe he'd put him somewhere so that he could listen to the whining of Sisyphus, Tantalus and Medea all at once; while also suffering his own punishment. Maybe play on loop the sounds of nails on chalkboard. Nico mused over his options, from gruesome to just outright cruel.

A mildly terrifying smile crept across his face as he continued to contemplate the doorknob-less door.


	5. Chapter 5

Nico wrapped shadows around himself as he hefted the scythe. Because he was temporarily doing Thanatos's job, he had to look the part. And Thanatos was going through a ' _funny_ ' stage. So Nico, feeling like an idiot, was forced to wear a long black cloak that covered his face and dragged on the floor and to carry a grim reaper scythe. It was stupid. His own sword would have worked just fine, but his father insisted. He tapped at the screen in his hand again before shadow traveling inside. He stumbled into the hallway, a little tired. He took out a flask of nectar and took a sip.

The godly drink reminded him of his first birthday cake, that slice of blue cake he'd eaten over the summer with Percy when he had first come up with his crazy half baked plan to save his hero. Nico's heart skipped a beat as he stuffed the flask back into his pocket. He took a deep breath and shadow travelled inside.

The house was creepy. And that was saying something, considering he lived in the Underworld part time. It might have been beautiful once, but now the long hallway Nico stands in is clearly falling apart. The dark wallpaper is peeling away from the walls, dusty portraits line the walls and the chandelier is dripping cobwebs rather than light. Right next to where Nico is currently standing is what looks like an umbrella stand, but when Nico peered at it, he could see it was a severed leg of some monster. Nico frowned.

_'That's a terrible spoil of war. Why just the leg?'_  He wondered. He looked up to see a group of shocked teenagers. Nico tilted his head sideways, examining each of them. There were four redheads, clearly related, a girl with bushy brown hair and a scrawny boy with messy black hair. None of these kids matched the description he had for the miscreant Tom Riddle. The brown haired girl grabbed hold of one of the redheads and the black haired boy before backing away slightly. The two taller redheads, they looked like twins, took out sticks and were pointing them at him.

"Moody!" The girl with brown hair yelped. Nico ignored them as he started to walk into the house. He could sense the soul somewhere nearby. But it felt wrong. Disjointed. Incomplete. Nico's eyes widened.

_"Di Immortales_!" He swore. If what had he think had happened, happened, this errand would be more of a waste of his time than he expected it to be. Loud thumping came up a staircase behind the group of teenagers edging away from him. A group of adults burst through, all of them pointing sticks at him. Nico felt a hum of power, not unlike the stones that made up the Hecate cabin. It was faint, so faint he didn't think he would have noticed if it wasn't for the fact that half a dozen people were all exuding the same power. Nico removed the IPad from his pocket.

"Look I'm just here to collect…." Nico swore as he tapped the wrong button. Now the screen was covered in photographs of last week's judgments. One of the men seemed to be shouting at him but Nico ignored him. He growled, shaking the tablet. He was convinced the damned thing was possessed. Maybe Melinoe was playing another trick on him. His immortal half sister was nasty like that. He shook it harder.

"BOY!" A grizzled old man covered in scars roared in his face. Nico looked up, startled. He hadn't realized how close he had gotten until the man had put his stick so close to Nico's eye. The demigod leaned back slightly pushing the stick to the side.

"Look, I'd like to keep my eye, thank you very much. Just because you lost yours doesn't mean I want to lose mine." He muttered. A tall man, who looked slightly ill, snorted loudly.

"How did you get in here? What do you want? Who do you work for?" The grizzled man snarled at him. Nico glanced out, still shaking the malfunctioning IPad.

"I work for my father. I'm here to collect a soul." He said matter of factly. He looked down at the IPad as he let out a whoop of triumph.

"Aha! Take that you…." Nico let out a torrent of swear words in English, Italian, Ancient Greek and Latin. An older woman, with red hair and worn clothing pushed her way forward.

"Now I don't care who you think you are young man, you do not use that kind of language in this house!" She scolded. Nico cut himself off, feeling slightly guilty. A tired looking man placed a hand on the woman's shoulder. Nico froze as he took in the man's appearance.

_Werewolf._

Nico tensed, ready for a fight. The whole room seemed to notice the shift in his mood. The grizzled man yelled out something he didn't quite catch, but a bright red light burst from the end of his stick that hit Nico. For a moment Nico felt as though he had a bit of vertigo, but then the sensation cleared away. He shook his head out like a wet dog.

"Look, I just want to collect this soul and go home. I was supposed to be on vacation right now." Nico said clearly. The grizzled old man just growled at him.

"What  _are_  you?" Nico sighed, putting the IPad in his pocket.

"I am a reaper of souls." He said vaguely. That was usually enough to frighten the mortals into submission. But here it seems it wasn't with these ones. The sick looking mortal muttered something while pointing his own stick at the ugly spoil of war.

" _Wingardium Leviosa._ " To Nico's utter shock the leg floated into the air and slammed into him. His small body went flying across the hall, slamming into a wall. Nico snarled slightly and stood up. He waved his hand, a rush of shadows going down the hall. It wouldn't hurt them, but it would distract, and frighten, the mortals. He stood up, wobbling on his feet. He must have hit his head harder than he thought. He stumbled wearily to the side, gripping at the wall. More colored lights flew out towards him. Brave mortals.

"Well than. If that's how you want to play." He growled. Using the shadows, he summoned his stygian iron sword. But that little use of his powers, coupled with his rather long day on top of the solid hit that leg got in, Nico finally collapsed.


	6. Chapter 6

When he finally came to, Nico found himself tied to a chair in a dark kitchen surrounded by arguing adults. He rolled his eyes and leaned back. The idiots had only tied his wrists to the slats of a  _very_ rickety old chair. He counted down silently before abruptly standing and crashing down as hard as he could on the chair. It broke apart immediately.

Nico was a little surprised that his plan had worked so easily. He'd thought it would be harder. Clearly the wizards, Nico finally remembered what Hecate's pets called themselves, hadn't been expecting him to escape quite so easily either. It would have been nice if Tom Riddle's file had mentioned that little detail. Would have made the whole scenario that much easier. He stood up, brushing the dust off his clothing, ignoring the wizards who were staring at him open mouthed. Only the grizzled one who'd nearly poked his eye out had bothered to take out his stick, pointing it steadily at him.

"Look I'm just here to collect a Tom Riddle's soul. My father is very unhappy with him." All the adults exchanged startled looks with each other. Nico shifted on his feet, swaying slightly. He really hadn't slept enough to recover all his energy.

"There is no Tom Riddle here. Where did you hear that name?" An old man with twinkling blue eyes and sweeping robes asked pleasantly, though there was an edge of steel hidden in his voice. The old man held himself with the demeanor of someone used to power, and responsibility. Nico patted his coat. The wizards had removed his large robe, revealing his aviator jacket and jeans. The IPad, along with his extra nectar and ambrosia were in the pockets of the robe.

"Can I have my stuff back? I'm really tired, and it's been a long day." Nico said, ignoring the question. The grizzled man from before snarled at him.

"I don't know what manner of dark creature or wizard you are but you  _will_  tell us everything." The ominous  _or else_  was heavily implied. Nico swayed a little more.

"Well I can't tell you anything if I pass out again. I need my things to get better." Nico explained patiently. The older woman he had seen earlier hurried forward, brandishing her stick.

_'Wand.'_  Nico remembered from his few lessons at camp. She waved it and _poof_ the chair reassembled itself. Nico slumped back down as the balding redhead he suspected was her husband brought the heavy cloak to him. Nico patted through the pockets, not surprised that the wizards had removed the knives inside. He managed to find the pocket with his medical supplies after practically turning the whole cloak inside out. He unscrewed the cap to the flask of nectar and brought it to his mouth.

"Aren't you a bit young to be drinking?" The sick looking man asked wryly. Nico rolled his eyes and took a careful sip. Birthday cake.

"It's not alcohol. It's medicine, of sorts." He replied. Then Nico thought about the Lotus.

"Besides, technically I am more than old enough to drink." He took another sip of liquid birthday cake before screwing the cap back onto the godly drink. The grizzled old man narrowed his eye in suspicion.

_"Specialis Revelio."_  He muttered while jabbing his wand at him. Nico blinked. Was that supposed to do something?

"Boy, that would have revealed if you had any enchantments on you. You, are nothing more than a child wielding weapons you have no business touching. How did you find this place? If you're in trouble son, we can help you." The man grumbled, both his rather unsettling eyes fixed on him, his gaze seemingly softened.

"Not in trouble yet, all I need to do is find Tom Riddle's soul. Really. Swear on the Styx." Nico said dismissively. It was then the old man with twinkling eyes and half moon spectacles looked mildly startled.

"And where, pray tell, did you learn that particular oath? It's not one to be made lightly." The whole room stiffened as one. It seemed the old man, whose power seemed to ding a little higher on Nico's radar than the others, was their leader. The leader's suspicion and curiosity changed the room back into an interrogation.

"My father." Nico answered warily, wondering what the old man knew. And  _why_  the old man knew what he meant when Nico had sworn on the Styx.

"And is your father, perhaps somewhere many of us would prefer not to think of?" Nico smirked as he thought about all the different aspects of the Underworld. There was nothing to be feared of the Lord of the Underworld as long as you didn't do anything bad. The afterlife, while rather boring for most, wasn't actually a bad place. And Hades, while mostly indifferent to his subjects, wasn't a cruel god.

"I think the only people who need to fear my father, are those who know that they have something to fear." Nico replied wryly, recognizing the feel of the older man's power. It was almost like being around the legacies at Camp Jupiter. The old man was powerful because he had godly blood somewhere in his ancestry. Likely Hecate; or Trivia, as the Romans called her. Definitely at least three or four generations removed. Nothing that any monster would smell, but enough to boost his wizardly magic. Probably a prodigy in the wizarding world.

With a genial smile, the old man waved his wand and the rickety chair Nico was seated on transformed into something far more comfortable. The room relaxed as one. 

"Well said. Death, after all, is simply the next great adventure." He said, folding long fingers against his chin. Nico frowned and shook his head.

"I really hope that's not what he's off doing. I'm supposed to be on vacation and I'm tired of running his errands." That got him a few startled looks. Waving it off, he frustratedly began to tap on the IPad.

"Look, I get it you're all busy and fighting and whatnot. But I just need to collect this soul and then I can go on my way. I need to get back home. If I'm not there the Stoll brothers will probably try to raid my cabin. I don't want to scrape flambeed idiot off the walls again." There was a strangled gasp at that comment but he ignored it as he began to scroll through the information he had. It seemed to be updating and changing every few seconds. The screen kept resetting to the top and Nico was nearly growling as he fought with the technology. The older balding red headed man came closer and closer, a childlike fascination in his wide eyes.

"You are a muggle, of a sorts. Could you possibly tell me what the exact purpose of a rubber duck happens to be?"

"Arthur!"


	7. Chapter 7

Nico was thoroughly confused. It seemed that while the old man, whose name was _Dumbledore_ , knew of the gods, none of the others did. Which made his current situation incredibly difficult. He had to collect Riddle's soul. Who was now calling himself Voldemort, and had followers who, ate... death? It was all very strange, and making his life more complicated than it needed to be. On the other hand, at least he'd finally been introduced to everyone.

Currently all the adults were arguing over if he could join their secret club; the one dedicated to defeating the very mortal he'd been sent to kill.

"No! He's far too young to join the Order!" Mrs. Weasley protested, the older red headed woman he had first met, turned to face Nico.

"What about your parents! What if you died!" She asked, pleadingly. As though he would take her side. Nico snorted.

"They'd ground me for coming home without a body." Everyone looked rather taken aback. None of them had been expecting an answer, let alone one so relaxed. Nico raised an eyebrow.

"I came to reap a soul. What were you expecting? For me to have normal parents who baked me cookies and worried about my grades?" The grizzled man with the scars, Moody, stumped forward.

"Boy, we need the help. Not going to sugarcoat that fact. But this is a war. People die. You could die. Do you understand this risk? You're not of age, you could, and should, leave the fighting to the adults." Mrs. Weasley looked about ready to explode at the idea that Moody was giving Nico the choice to join up. He shifted in his chair, as his ADHD acted up. He shook his head, an amused expression crossing his face.

"A lot of things could kill me. A lot of things have tried. Hellhounds, Titans, A very dedicated duck. This isn't exactly original. Try again." Nico smirked at the startled Moody. He'd seen right through the scare tactic. Nico sighed, glancing away.

"Look, battle, war, there is nothing glorious about it. I know this already. There is no glory when you're knee deep in blood and viscera, surrounded by the bodies of your friends. It's nothing but pain and death. But your war is hardly begun. I have the power, and the resources to help you end it, and end it quickly. So here is where you make a choice," He crossed his arms, leaning back in the comfortable chair, dark eyes boring into the bright blues of Dumbledore.

"Either I fight with you, using your knowledge and resources; which I freely admit I need. Or I fight without you, going with what I can find, and then fighting by the skin of my teeth. Either way, Riddle's soul is mine. The only thing that changes is how long it takes, and how many innocents have to die along the way." Their gazes locked, dark eyes against bright blue, young and old. The crazy part was, Nico was certain that his eyes were older. And maybe literally too. The old man nodded slowly.

"Well, it appears as though young Mr. Di Angelo had made his decision. Welcome to the Order of the Phoenix." Nico smiled even as Mrs. Weasley let out an outraged squawk.


	8. Chapter 8

Nico sighed, as he picked at the food that had been heaped onto the plate in front of him. The meeting had wrapped up quickly after he’d been welcomed in, and now it was dinner time. The other children from before had been welcomed back downstairs, and had been informed that Nico  _ was _ in fact supposed to be there. He just happened to be early; and being such a mysterious ally, nobody had known what he looked like, which was what lead to all the confusion in the first place. 

Nico struggled to ignore the uncomfortable prickling sensation in the back of his head as he ate. The scrawny boy with messy black hair was staring at him. So were the rest of the children, but the black hair boy  _ felt _ wrong. Death hung around him like a cloud, but it had nothing to do with his soul. And he reminded Nico of Percy. 

His heart did another  _ skip-bump _ even as he pushed away the feelings that thinking about the son of Poseidon always brought. 

Finally he’d had enough. Nico glanced up at the table of suspicious faces. 

“What.” He snapped. The whole table flinched away from his glare. A pang of pain shot through him briefly but Nico pushed the feeling away. He was the son of Hades; no one would accept him. Even weird mortals could feel the aura of the Underworld that clung to him like a cloak. Finally the girl with bushy brown hair spoke up. 

“Who are you?” She asked him quickly. Nico gave her a dull glare before answering.

“Nico.” He answered shortly. The girl smiled at him, a little nervously, but Nico could appreciate the effort. 

“I’m Hermione, Hermione Granger. This is Ginny,” She gestured to the red headed girl sitting next to her, and Ginny nodded at him while taking a sip from her cup. Hermione kept going, her voice growing more confident with every word.  

“The twins are Fred,’ one of the older redheads waved, “and George,” the other one waved. The two of them had matching trouble making grins, not unlike the Stoll brothers at CHB. He made a mental note to never let either of them near enough to pickpocket him. He carried plenty of things that were dangerous to an ordinary demigod, let alone a pair of mortal troublemakers. 

“Ron is down there at the end” The last redhead didn’t bother looking up as he continued to shove a truly impressive amount of food down his throat. Hermione finally pointed to the boy sitting across from him. 

“And of course, that’s Harry.” She concluded, and the black haired boy sitting across from him nodded shortly, green eyes glittering with suspicion. Hermione said  _ Harry _ the way most demigods would say  _ Percy _ . Like he should already know who he was, and that he was important. Not just important, but someone to look up to, a  _ hero _ . The leader. He filed that information away for later. Nico gave short nods in greeting at each introduction but mostly focused on eating the food in front of him. It was better than anything he’d eaten in a long time, especially because he’d been spending so much time in the Underworld lately. Keeping the busiest realm under control was a lot of work. His dad never gets enough credit for being Lord of the Underworld. 

An odd silence fell over the table. Nico looked up to see surprise etched into every expression. 

“What?” He groused, setting his fork down, but keeping a tight hold of the knife in his hand. No matter what Dumbledore had told him about his safety inside the walls of number 12, he wasn’t going to take the old man at his word. No, Nico needed to be careful, and on guard. None of the order members besides the old man trusted him; he’d heard whispers of dark magic and evil coming from the adults before the other children arrived. Then the room had lightened significantly, the adults doing everything they could to protect the children from the darkness of the war effort. Because that’s what they were doing, waging a secret war. 

“No, nothing I suppose. It’s just most people usually react quite strongly to meeting Harry, and you… didn’t.” Nico shrugged. Sirius Black had taken him aside a given him a brief overview of Harry, and what made him so special, but Nico didn’t particularly care. He’d fought against the Titans with his father, commanded an army of dead and battled with monsters the wizards couldn’t even imagine. Tom Riddle, or Voldemort, didn’t scare him. 

“Anyways….” Hermione trailed off awkwardly. Nico just took another bite. He had no interest in keeping up the conversation. He just wanted to complete his mission and go home. 

Speaking of which, Nico knew that Tom Riddle, or at least a piece or two of his soul was in that house. He could still feel it, even as it was mostly overwhelmed by the sheer wrongness of Harry. Even though there was, superficially at least, nothing wrong with him. He knew he’d need to investigate more closely after everyone went to sleep. 

“Why did you decide to drop by London?”  Harry asked abruptly. “What are you doing for the Order? You’re American, and Voldemort hadn’t really gone outside of England the last time he was in power.” Nico raised an eyebrow slowly at the aggressive questioning. 

“Job for my dad. Volde-whatever pissed him off. I’m here to make sure he is punished accordingly.” 

“And he sent you?” Ron scoffed incredulously. The rest of the table ranged from surprised to horrified to outright disbelief. 

“Me.” Nico agreed. He stood up from the table, picking up his empty plate and carrying it over to the sink. 

“I’m going to sleep now. Jetlag, you know.” He offered as a weak excuse. Without waiting for a response he left the room, heading up the stairs aimlessly. He figured, now that the wizard people had accepted him as a non-threat, he could leave now. Nico would find some nice graveyard nearby to sleep in, maybe check in with Hazel and have a quick chat with the local ghosts and dead. Maybe then he could get some confirmation to his suspicions. 

Stupid wizards, dizzy with power from Hecate, had found endless numbers of way to avoid death for as long as possible, generally by extending their lives for as long as possible. Most of the time, they weren’t really escaping death, just prolonging the inevitable. That wasn’t a crime. Hades didn’t care if someone decided to live until they were four month, or four hundred. Eventually, they still died. No the problems lay with other tactics. 

Like what Tom Riddle did. He tore his soul, his shade, into several pieces and tied them to the world of the living. Even if he was killed, he wouldn’t die. And that was a problem. Nico was going to have to go and systematically track down and collect all those pieces, sending them to the Underworld before killing Tom Riddle. Then the death cheater would be punished appropriately for the rest of eternity. 

“Nico, where are you going?” Came a voice behind him. He turned around to see the red haired girl. Ginny. 

“To find someplace to sleep.” He said plainly, one hand on the door. 

“Mum said to show you upstairs. You’re staying here, it’s not safe out there.  Especially if You-Know-Who is targeting your Dad. She also said to tell you that Dumbledore wants to talk to you in the morning.” The girl turned away, starting up the rickety staircase, passing the withered heads without waiting for him. After only a momentary pause, Nico followed behind her. It might be nice to sleep in an actual bed for once. 


End file.
